A blog about technologies, science, books and other stuff, especially science fiction

Graphene to improve seawater desalinization technology

A graphene membrane, in red, with silicon atoms in yellow (Image courtesy Oak Ridge National Laboratory, US Dept. of Energy. All rights reserved)

An article published a few days ago on the journal “Nature Nanotechnology” describes a research on a new technique for the desalination of seawater using a porous membrane made of graphene. This material is considered revolutionary in the field of electronics for its characteristics but research like this are showing that it can also be very useful in other fields. In the case of desalination, its use can make it much more efficient needing much less energy to get drinking water.

Only 1% of the water existing on Earth is drinkable. March 22 was the World Water Day and on that occasion information were provided about the severity of the problem of the access to drinking water in some parts of the world. Over 700 million people have no access to drinking water and are therefore constantly at risk of diseases and poisoning because they have to drink contaminated water.

Desalinating seawater could be a huge help, also for agriculture, helping many hungry people to grow food to survive. The problem is that desalination is a process that requires a lot of energy and typically the people who need it are the same ones who don’t have access to a power grid to get it.

The experiment conducted in the USA by the Oak Ridge National Laboratory shows that the use of graphene can make the desalination process much more efficient. Creating microscopic pores in graphene allows to use it as a filter for seawater. It becomes a porous membrane which doesn’t allow the salts to pass through but only the water molecules in a much more efficient way than the techniques currently used.

The graphene sheets have the thickness of a single atom but are flexible and strong. Their characteristics make graphene porous membranes excellent for desalination. In fact, they’re more permeable than other polymers making the separation of water from the salts quicker. The complete process is more complex but the point is that the experiment was a success.

It’s not the first time that an experiment exploits these properties of graphene. In recent months, a project was announced to use this material to purify water polluted by hydrocarbons. This shows that graphene has a really huge potential in many fields and will not only be the basis for a new generation of electronic devices but can also increase the quality of life of many people in the world.